resistance to trampling wear is the resistance of a surface to wear and tear (for unglazed tiles) or to change its appearance (for glazed tiles). According to UNI EN norms, abrasion resistance is classified with PEI grades, where PEI 1 corresponds to the lowest resistance and PEI 5 corresponds to the most resistant tiles. For unglazed tiles, abrasion resistance increases with the decrease of water absorption therefore it is high in the case of porcelain stoneware. The abrasion resistance value can also change depending on the treatments carried out on the tile surface: in the case of terracotta tiles, for instance, the impregnation using natural or synthetic substances and for porcelain stoneware any polishing treatment. For glazed tiles, abrasion resistance exclusively depends on the glaze: light colour glazes tend to show the effects of use more, also due to their more complex cleaning.

the key safety feature for a tiled surface is its slip resistance. A slippery surface creates an architectonic barrier making walking on the surface difficult and treacherous, particularly for those suffering from either a permanent or temporary physical disability.

stage of the productive process that has the function of drying the ceramic mix (slip) following the wet milling of raw materials, in order to obtain atomized powders that will undergo a semi-dry pressing. The slip is sprayed in a hot air current, therefore the drops dry quickly and become spherical grains that are internally hollow and that contain a moisture residue (ranging from 4 to 8%) as this is useful as a lubricating agent during the following pressing procedure.